/**
 * Definition for singly-linked list.
 * struct ListNode {
 *     int val;
 *     ListNode *next;
 *     ListNode() : val(0), next(nullptr) {}
 *     ListNode(int x) : val(x), next(nullptr) {}
 *     ListNode(int x, ListNode *next) : val(x), next(next) {}
 * };
 */
class Solution {
public:
    ListNode* addTwoNumbers(ListNode* l1, ListNode* l2) {
        ListNode*newhead=new ListNode(0);
        ListNode*cur1=l1,*cur2=l2;
        ListNode*prev=newhead;
        int t=0;
        while(cur1||cur2||t)
        {
            if(cur1){
            t+=cur1->val;
            cur1=cur1->next;
            }
            if(cur2){
                t+=cur2->val;
                cur2=cur2->next;
            }
            prev->next=new ListNode(t%10);
            prev=prev->next;
            t/=10;
        }
        prev=newhead->next;
        delete newhead;
       
        return prev;

    }
};
